Apparatus for drilling holes utilizing pulsed jets of liquid charge material

ABSTRACT

Apparatus for drilling holes in a formation utilizing pulsed jets of charge material. A housing encloses means for generating pulsed jets of, for example, liquid charge material. One or more acceleration bores extend out the housing in a conical pattern. One or more longitudinal grooves are included in the housing, and means are provided for impelling spent charge material, formation chips, mud, etc. from the hole and out through the longitudinal grooves. A single acceleration bore can have one or more outlet bores angled therefrom to cause a rotational force in the housing in response to expelling of pulsed jets of charge material out the outlet bores. The housing can be made of a first portion with the acceleration bore therein and a nozzle portion with the outlet bores therein and rotatably coupled to the first portion so that only the nozzle portion rotates in response to expelling of pulsed jets. Smoothing tips can extend from the housing to smooth the hole as the housing rotates.

United States Patent [1 1 [11] 3, Hall et a1. [45] Dec. 23, 1975 APPARATUS FOR DRILLING HOLES UTILIZING PULSED JETS OF LIQUID CHARGE MATERIAL [75] Inventors: James M. Hall, Gaithersburg, Md.;

Louis L. Clipp, McLean, Va. [73] Assignee: Exotech, Incorporated,

Gaithersburg, Md.

[22] Filed: June 11, 1973 [21] Appl. No.: 368,984

Related US. Application Data [63] Continuation of Ser. No. 153,582, June 16, 1971.

[52] US. Cl 175/422; 175/67 [51] Int. C1. E21B 7/18 [58] Field of Search 175/56, 67, 422; 299/177 [56] References Cited UNITED STATES PATENTS 3,251,424 5/1966 Brooks 175/56 3,384,192 5/1968 Goodwin et a1. 175/67 3,520,477 7/1970 Cooley 299/17 X 3,539,104 11/1970 Cooley 175/67 X 3,576,222 4/1971 Acheson et a1. 174/422 X 3,620,313 ll/l97l Elmore 175/67 X 3,645,346 2/1972 Miller ct a1. 175/237 Primary ExaminerFrank L. Abbott Assistant Examiner-Richard E. Favreau Attorney, Agent, or FirmMorton, Bernard, Brown, Roberts & Sutherland [57] ABSTRACT Apparatus for drilling holes in a formation utilizing pulsed jets of charge material. A housing encloses means for generating pulsed jets of, for example, liquid charge material. One or more acceleration bores extend out the housing in a conical pattern. One or more longitudinal grooves are included in the housing, and means are provided for impelling spent charge material, formation chips, mud, etc. from the hole and out through the longitudinal grooves. A single acceleration bore can have one or more outlet bores angled therefrom to cause a rotational force in the housing in response to expelling of pulsed jets of charge material out the outlet bores. The housing can be made of a first portion with the acceleration bore therein and a nozzle portion with the outlet bores therein and rotatably coupled to the first portion so that only the nozzle portion rotates in response to expelling of pulsed jets. Smoothing tips can extend from the housing to smooth the hole as the housing rotates.

9 Claims, 4 Drawing Figures 3 L I 7L us. Patent 1366.23, 1975 3,927,723

2//%//;3% |3o|22 INVENTZ;S-I

MES M. HALL. Q

LOUIS L. CLIPP APPARATUS FOR DRILLING HOLES UTILIZING PULSED JETS OF LIQUID CHARGE MATERIAL This is a continuation, of application Ser. No. 153,582, filed June 16, 1971.

The present invention pertains to a liquid powered drill. More particularly, the present invention pertains to a drill capable of forming holes in rock and utilizing as a drilling substance a liquid such as water.

In many geological activities, such as mining and well construction, drilling of holes into earth formations is desired. Such holes are often filled with explosives which are then detonated to shatter large portions of the earth formations. Other such holes are used within mines for the installation of roof bolts. By way of illustration, the holes may be 1 to 2 inches in diameter and of any required length, for example a length in the range of from about 6 inches to about 30 feet. The holes frequently must go through rock and other hard formations. Drills are available for forming such holes. However, such drills have a relatively short life due to the hard wear experienced in drilling through rock formations. When it is necessary to replace such a drill bit, the entire drill assembly must be removed from the hole. If the hole is of considerable depth, the removal, drill replacement, and reinsertion can be an extremely time-consuming task.

There recently have been developed so-called water cannons, capable of expelling pulsed jets of liquid or gel charge material at pressures sufficient to fracture rock formations, for example pressures in the order of 300,000 to 1,000,000 pounds per square inch (p.s.i.). Use of such water cannons to fracture rock formations offers several advantages. Such devices can utilize, as a charge material, water which generally is readily available at low cost. The direction of the jet pulse can be easily controlled, and so the cannon is a relatively safe device. A water cannon can be operated with a high repetition rate, making it possible to apply several high pressure jet pulses in rapid succession. Examples of such water cannons are found in copending U.S. Pat. application Ser. No. 135,119 filed Apr. 19, 1971, now U.S. Pat. No. 3,712,543 issued Jan. 23, 1973, and copending U.S. Pat. application Ser. No. 135,120 filed Apr. 19, 1971, now U.S. Pat. No. 3,708,121, issued Jan. 2, 1973, both by James M. Hall and Louis L. Clipp.

The present invention is a drill capable of drilling holes through hard formations such as rock and utilizing pulsed jets of a charge material such as water as the drilling medium with the result that there is no drill bit to wear out and require replacement. In accordance with the present invention, there is provided apparatus including a charge chamber adapted to receive a charge of material and communicating with one or more acceleration bores extending from the charge chamber in a conical pattern. A piston acts on charge material in the charge chamber to expel the charge material out the acceleration bores. A single acceleration bore can extend from the charge chamber and communicate with one or a plurality of outlet bores spaced about the outlet end of the apparatus. The communication between the acceleration bore and the one or more outlet bores can be angled so that the charge material flowing through the outlet bore imparts an opposite rotational force to the apparatus outlet end. The resulting rotation of the outlet bores causes the apparatus to drill a hole of substantially the diameter of the device or of a slightly greater diameter. Longitudinal grooves are provided spaced about the periphery of the apparatus through which spent charge material, rock chips, mud, etc. are impelled for removal, either under urging of a vacuum applied to the longitudinal grooves or of air provided through an additional opening.

These and other aspects and advantages of the present invention are more apparent in the following detailed description and claims, particularly when considered in conjunction with the accompanying drawings in which like parts bear like reference numerals. In the drawings:

FIG. 1 is a broken sectional view illustrating apparatus in accordance with the present invention and is taken along line 11 of FIG. 2;

FIG. 2 is an elevational view of the embodiment of apparatus in FIG. 1;

FIG. 3 is a broken sectional view of an embodiment of apparatus incorporating alternative features in accordance with the present invention and is taken along line 33 of FIG. 4; and

FIG. 4 is an elevational view of the embodiment of apparatus in FIG. 3.

.FIG. 1 illustrates in simplified form, apparatus for forming pulsed jets of charge material and expelling the jets through a plurality of openings to drill through earth formations and other such material. Charge material is provided from a source 8 through inlet 10 in housing 12 to charge reservoir 14 which communicates with acceleration bores 16 passing through housing 12. Piston 18 is positioned adjacent charge reservoir 14 and preferably includes sealing means such as piston ring 20 adjacent its forward end. Charge material is supplied from source 8 through inlet 10 to charge reservoir l4. Piston 18 is then actuated, moving into charge reservoir 14. Piston 18 closes off inlet 10, and piston ring 20 assures that charge material does not leak from charge reservoir 14 out inlet 10. The charge material is expelled out acceleration bores 16 as pulsed jets. Preferably the diameters of acceleration bores 16 decrease along their length to cause the charge material velocity and pressure to increase as it exits.

The above is a somewhat simplified description of water cannon construction and operation. A more detailed description is contained, for example, in copending U.S. Pat. applications Ser. Nos. 135,119 and 135,120, both filed Apr. 19, 1971 by James M. Hall and Louis L. Clipp.

Acceleration bores 16 extend from charge reservoir 14 in a conical fashion and terminate in outlet openings 24 adjacent the periphery of outlet end 26 of housing 12. The number of acceleration bores 16 can vary from one to any number, e.g. six as shown. One -or more longitudinal grooves 28 are provided on the outer surface of housing 12 and extend the full length of the housing to communicate with a vacuum source 29, such as a vacuum pump.

Pulsed jets of charge material, resulting from impacting of piston 18 on charge material within charge reservoir 14, pass down acceleration bores 16 and impact upon the earth formation with a high pressure, for example a pressure in the range of from about 300,000 p.s.i. to about 1 million p.s.i. As a consequence, the earth formation is shattered. A vacuum is applied from vacuum source 29 to each longitudinal groove 28 to impell spent charge material, rock chips, mud, etc. from adjacent outlet openings 24 in the hole as it is If desired, housing 12 can be rotated during operation, either by mechanical means from its rearward end or due to reaction forces resulting from passage of the pulsed jets through properly oriented acceleration bores 16 in a manner similar to that of the embodiment of FIGS. 3 and 4 described hereinafter.

Housing 12 is of a size dependent upon the desired size of the hole to be drilled. Typically, housing 12 might have a diameter in the range of from about 1 inch to about 2 inches and a length in the range of from about l foot to about 30 feet.

FIGS. 3 and 4 depict an embodiment of apparatus incorporating alternative features in accordance with the present invention. As seen in FIGS. 3 and 4, housing 112, with a single central acceleration bore 116 therein, includes nozzle portion 130. Housing 112 includes means for generating a pulsed jet similar to charge reservoir 14 and piston 18 of FIG. 1, with charge material provided from source 108 through inlet 110. Within nozzle portion 130, acceleration bore 116 terminates in one or more outlet portions 122. Outlet portions 122 are arranged at an angle a with respect to acceleration bore 116. Angle a may be as great as to Each pulsed jet passing through outlet portions 122 and outlet openings 124 imparts an opposite reaction force to nozzle portion 130, causing the nozzle portion 130 to rotate with respect to housing 112.

One or more longitudinal grooves 128 extend the length of housing 112 and communicate with circumferential groove 132 at the interface of housing 112 and nozzle portion 130. Housing 112 includes a forwardly extending flange 134 including a lip 136 which fits snugly but slidingly within a corresponding circumferential recess in nozzle portion 130 to maintain housing 112 and nozzle portion 130 in engagement while permitting rotational movement therebetween. Circumferential groove 132 communicates with one or more longitudinal grooves 128 on the outer surface of nozzle portion 130. A second longitudinal bore 138 passes through housing 112 and communicates with annular groove 140 at the interface of housing 112 and nozzle porn'on 130. Annular groove 140 communicates with a second longitudinal bore 142 through nozzle portion 130. As the drill of this embodiment is operated, pressurized gas such as air is passed from source 144 through bore 138, annular groove 140 and bore 142 to irnpell spent charge material, rock chips, mud, etc. from within the hole being drilled and adjacent outlet openings 124 through grooves 128, 132, and 128 for discharge.

Outlet end 126 of nozzle portion 130 has extending therefrom one or more high strength tips 146 of, for example, tungsten carbide. The earth formation is broken up by the pulsed jets of charge material, and the hole is smoothed by tips 146 which readily cut the weakened rock or other material as nozzle portion 130 rotates.

Although the present invention has been disclosed with reference to preferred embodiments, numerous modifications and rearrangements could be made, and still the result would be within the scope of the invention.

What is claimed is:

1. Apparatus for drilling holes comprising:

a housing with a first end and a second end and having a longitudinal bore passing therethrough and having at least one acceleration bore passing thereinto from said housing second end and at an angle with respect to the housing longitudinal axis and having at least one longitudinal groove extending the length thereof;

first means for generating a pulsed jet of charge material for passage through the at least one acceleration bore;

a pressurized gas source adjacent said housing first end and coupled to the longitudinal bore for impelling material from said housing second end through the longitudinal groove to the housing first end whereby as a hole is drilled in a formation adjacent said housing second end by pulsed jets of charge material expelled out the at least one acceleration bore, spent charge material and formation chips are impelled from the hole through the longitudinal groove for discharge at the housing first end.

2. Apparatus for drilling holes comprising:

a housing with a first end and a second end and having at least one valveless acceleration bore passing thereinto from said housing second end and at an angle with respect to the housing longitudinal axis, said acceleration bore having no impediment to the flow of fluid therethrough, said housing having at least one longitudinal groove extending the length of said housing;

a single pulsed jet generator for generating a pulsed jet of charge material for passage through each acceleration bore in said housing located at said first end;

impelling means for impelling material from said housing second end through the longitudinal groove to the housing first end whereby as a hole is drilled in a formation adjacent said housing second end by pulsed jets of charge material expelled out each acceleration bore, spent charge material and formation chips are impelled from the hole through the longitudinal groove for discharge at the housing first end.

3. Apparatus as claimed in claim 2 in which said second means comprises a vacuum pump adjacent said housing first end and connected to the longitudinal groove.

4. Apparatus as claimed in claim 2 in which said housing has a single longitudinal acceleration bore therein and communicating with at least one outlet bore, each outlet bore passing out said housing second end and intersecting the acceleration bore at an angle a with respect to the housing longitudinal axis.

5. Apparatus as claimed in claim 4 in which angle a is an angle up to about 20.

6. Apparatus as claimed in claim 2 in which said housing includes a first portion having a single longitudinal acceleration bore therein and a nozzle portion having at least one outlet bore therein communicating with the acceleration bore, at an angle a, said nozzle portion rotatably coupled to said first portion.

7. Apparatus as claimed in claim 6 in which angle a is an angle up to about 20.

8. Apparatus as claimed in claim 6 in which said housing has a plurality of acceleration bores, each acceleration bore at an angle a with respect to the housing longitudinal axis.

9. Apparatus as claimed in claim 8 in which said housing further has a longitudinal acceleration bore. 1

UNITED STATES PATENT AND TRADEMARK OFFICE CERTIFICATE OF CORRECTION PATENT NO. 3,927,723 DATED December 23, 1975 INV ENTOR(S) 1 JAMES M. HALL & LOUIS L. CLIPP it is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 4, line 64, "claim 6" should read claim 2-.

Signed and Scaled this ninth Day of March 1976 [SEAL] Attest:

RUTH C. MASON C. MARSHALL DANN Artexting Officer Commissioner ofPatenrs and Trademarks 

1. Apparatus for drilling holes comprising: a housing with a first end and a second end and having a longitudinal bore passing therethrough and having at least one acceleration bore passing thereinto from said housing second end and at an angle with respect to the housing longitudinal axis and having at least one longitudinal groove extending the length thereof; first means for generating a pulsed jet of charge material for passage through the at least one acceleration bore; a pressurized gas source adjacent said housing first end and coupled to the longitudinal bore for impelling material from said housing second end through the longitudinal groove to the housing first end whereby as a hole is drilled in a formation adjacent said housing second end by pulsed jets of charge material expelled out the at least one acceleration bore, spent charge material and formation chips are impelled from the hole through the longitudinal groove for discharge at the housing first end.
 2. Apparatus for drilling holes comprising: a housing with a first end and a second end and having at least one valveless acceleration bore passing thereinto from said housing second end and at an angle with respect to the housing longitudinal axis, said acceleration bore having no impediment to the flow of fluid therethrough, said housing having at least one longitudinal groove extending the length of said housing; a single pulsed jet generator for generating a pulsed jet of charge material for passage through each acceleration bore in said housing located at said first end; impelling means for impelling material from said housing second end through the longitudinal groove to the housing first end whereby as a hole is drilled in a formation adjacent said housing second end by pulsed jets of charge material expelled out each acceleration bore, spent charge material and formation chips are impelled from the hole through the longitudinal groove for discharge at the housing first end.
 3. Apparatus as claimed in claim 2 in which said second means comprises a vacuum pump adjacent said housing first end and connected to the longitudinal groove.
 4. Apparatus as claimed in claim 2 in which said housing has a single longitudinal acceleration bore therein and communicating with at least one outlet bore, each outlet bore passing out said housing second end and intersecting the acceleration bore at an angle Alpha with respect to the housing longitudinal axis.
 5. Apparatus as claimed in claim 4 in which angle Alpha is an angle up to about 20*.
 6. Apparatus as claimed in claim 2 in which said housing includes a first portion having a single longitudinal acceleration bore therein and a nozzle portion having at least one outlet bore therein communicating with the acceleration bore, at an angle Alpha , said nozzle portion rotatably coupled to said first portion.
 7. Apparatus as claimed in claim 6 in which angle Alpha is an angle up to about 20*.
 8. Apparatus as claimed in claim 6 in which said housing has a plurality of acceleration bores, each acceleration bore at an angle Alpha with respect to the housing longitudinal axis.
 9. Apparatus as claimed in claim 8 in which said housing further has a longitudinal acceleration bore. 